How the claim is calculated
How the claim is calculated
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Detailed method (all tax years)
Steps
Calculate the percentage of your work space used for employment purposes
You must first get the area of both your work space and the total finished areas of your home.
Size of work space (designated room or shared area)÷Total finished area of home×100(to convert it into a percentage)=(A)Percentage of your home that you used as a work space (rounded two decimal places)For a description of the variables in this mathematical formula, refer to:
If you are working in a designated room
Since the room is used only for work, the percentage of your home used as a work space is also the percentage of your work space used for employment purposes. You can proceed to calculate your work-space-in-the-home expenses.
A = C
If you are working in a common (shared) area
You need to calculate the percentage of the work space that was used for employment purposes by providing the number of hours worked in that space within a calendar week (7 days or 168 hours).
#(hours worked in a work week)÷168(total hours in a week)×100(to convert it into a percentage)=(B)Percentage of the time the work space was used for work (rounded to two decimal places)You will now calculate the percentage of your work space used for employment purposes by multiplying these two numbers together.
(A)Percentage of your home that you used as a work space×(B)Percentage of the time the work space was used for work (rounded to two decimal places)×100(to convert it into a percentage)=(C)Employment-use percentage of the work space (rounded to two decimal places)For a description of the variables in this mathematical formula, refer to:
Calculate your work-space-in-the-home employment-use amount
You will need to first add up all of your eligible work-space-in-the-home expenses (where applicable) you paid for the period(s) you worked more than 50% of the time from home for at least four consecutive weeks for the tax year you selected.
Electricity, heat, water, and home internet access fees+Rent (only employees who rent their home)+Maintenance costs paid that affect the entire home (for example, furnace repairs)+Home insurance (only commission employees who own their home)+Property taxes (only commission employees who own their home)+Other home expenses that include the work space=(D)Work-space-in-the-home expenses paid for the entire homeFor a description of the variables in this mathematical formula, refer to:
You will now calculate the portion of these expenses to claim based on what you determined to be the employment-use percentage of your work space.
(D)Work-space-in-the-home expenses paid for the entire home×(C)Employment-use percentage of the work space=(E)Employment-use amount of work-space-in-the-home expenses for the entire homeYou must also calculate the portion of the maintenance costs paid that affect only the work space (for example, purchase of light bulbs).
For a designated room
Maintenance costs paid for the work space only×100%=(F)Employment-use amount of maintenance costs for the work space onlyFor a common (shared) area
Maintenance costs paid for the work space only×(B)Percentage of the time the work space was used for work=(F)Employment-use amount of maintenance costs for the work space onlyFor a description of the variables in this mathematical formula, refer to:
Finally, you add the two expenses together.
(E)Employment-use amount of work-space-in-the-home expenses for the entire home+(F)Employment-use amount of maintenance costs for the work space only=(G)Total employment-use amount (line 48 on Form T777 or line 12 on Form T777S)If you are only claiming home office expenses for 2020, 2021, or 2022 using Form T777S, continue to Step 3.
Calculate your supplies and other expenses subtotal (line 3)
To complete Form T777S, you will need to add together all eligible office supplies and certain phone expenses you paid.
Office supplies (e.g. postage, stationery, ink cartridges, other office supplies, etc.)+Other expenses (employment use of a cell phone, long distance calls for employment purposes, etc.)=(H)Supplies and other expenses subtotalFor a description of the variables in this mathematical formula, refer to:
Calculate your maximum deduction for work-space-in-the-home expenses
To determine if you have any expenses to carry forward and to calculate the final work-space-in-the-home expenses you can claim, you must provide your employment income and the amount of certain other deductions.
Employment income (box 14 of your T4)−(H)Supplies and other expenses subtotal−Annual union, professional, or like dues (line 21200 from your return)−Registered Pension Plan (RPP) deduction (line 20700 of your return)=(I)Maximum deduction for work-space-in-the-home expensesCalculate the amount to carry forward
To calculate any amount to carry forward, you must subtract your maximum deduction for work-space-in-the-home expenses from the total employment-use amount of the expenses you paid.
(G)Total employment-use amount (line 12 on Form T777S)−(I)Maximum deduction for work-space-in-the-home expenses=(J)Total amount to carry forward (if negative, enter "0")Calculate the total home office expenses you can claim
To calculate the total home office expenses you can claim, you must add up a few of previous amounts you have calculated.
(H)Supplies and other expenses subtotal+The work-space-in-the-home expenses entered on line 9945 of Form T777S, which is the lesser of either:(G)Total employment-use amount(I)Maximum deduction for work-space-in-the-home expenses=(K)Total home office expenses you can claim, which you enter on line 9368 of Form T777S and on line 22900 of your return
Temporary flat rate method for 2020, 2021, and 2022
For a description of the variables in this mathematical formula, refer to: